There are always those adventurous souls who take an over-night ferry to Le Havre and arrive in the South of France within a day. We would suggest however, that if you want to drive, a morning crossing to Northern France, the motorway via Reims and an overnight stop (in Burgundy) makes for a pleasant journey.
Alternatively, La Garde-Freinet is an easy 1½ hour’s drive from both Marseilles and Nice airports and 45 minutes from Toulon airport. These airports are well served by easyJet, Ryanair and British Airways.